Boom handling apparatus



G. W. MORK BOOM HANDLING APPARATUS Sept. 3, 1968 5 Sheets-Sheet l Filed DeC. 9, 1966 IVE NTOR G EORGE W. MORK ATTORNEY Sept. 3, 1968 G. w. MoRK BOOM HANDLING APPARATUS 5 Sheets-Sheet 2 Filed Dec. 9. 1966 INVENTOR GEORGE W. MORK AT TORN E Y Sept. 3, 1968 G. w. MoRK 3,399,785

vBOOM HANDLING APPARATUS Filed Dec. 9. 1966 5 Shee'cs-Shee'fI 5 INVENTOR GEORGE W'. MORK ATTORNEY sept 3, 1968 G. w. MoRK 3,399,785

BOOM HANDLING APPARATUS INVENTOR |7 GEORGE w. MoRK AT TORNEY G. W. MORK BOOM HANDL I NG APPARATU S sept. 3, 196s 5 Sheets-Sheet 5 Filed DEC. 9.' 1966 INVENTOR GEORGE W. MORK ATTORNEY United States Patent Office 3,399,785 Patented Sept. 3, 1968 3,399,785 BOOM HANDLING APPARATUS George W. Mork, South Milwaukee,` Wis., assignor to Bucyrus-Erie Company,.Soutl1 Milwaukee, Wis., a corporation of Delaware Filed Dec. 9, 1966, Ser. No. 600,541 9 Claims. (Cl. 212--39) ABSTRACT OF THE DISCLOSURE Two examples of cranes are disclosed, each having a boom with the boom foot movable between a traveling position ove-r the back of the revolving frame and an operating position at the front of the revolving frame. The boom foot in one is hinged to the ends of arms, the other ends of which are fastened to an hydraulically driven torque tube to swing the boom toot between its two positions. The boom foot in the other is mounted on endless chains which carry it between its two positions. An automatic, boom-stop cable, take-up drum is shown, also.

Background of the invention The present invention improves the essential operating characteristics of truck mounted cranes, although the invention will have application wherever the objects achieved by it can nd advantageous application. Heavy duty truck mounted cranes are in demand for their great versatility and mobility. To provide these advantages, a heavy duty crane must combine maximum height with minimum length in the traveling position for on-highway transport. To achieve maximum height, the boom obviously must be long, and it must be able to operate at the highest possible angle. The latter requires suicient reach to clear the cranes revolving frame and the truck chassis, and so the boom foot must be mounted at the very front of the cranes revolving f-rame. However, for on-highway use, the overall length of the truck and the crane with its lowered boom must be minimized to stayv within the statutory limits of the various states and countries. These advantages must also be achieved without sacrificing pay load handling capabilities, and therefore suitable boom structure and boom hoist and support means must also be provided. To achieve maximum mobility, the boom must be capable of being raised and lowered in a minimum amount of time with a minimum of labor.

To achieve those conflicting objects, the present invention mounts the boom foot on a conveyor member, such .that when the boom is in Ia working position, the boom foot is stabilized on the -front end of the cranes revolving frame, and when the boom is in a traveling position, the boom foot is suspended beyond the rea-r end of the revolving frame. By this device the boom provides a maximum reach beyond the front of the revolving frame, so that it may be operated at high angles. To convert the crane into the traveling position, the boom is lowered to a horizontal position, and the boom foot is moved rearward until it is suspended beyond the back end of the revolving frame. The revolving frame is then rotated to place the boom over the cab of the truck, thus minimizing the length of the overall vehicle, including the boom, for highway travel. In an existing crane, the boom foot is moved nearly twenty feet between the working and traveling'position, thus shortening the overall vehicular length by the same amount.

The general idea of moving the boom foot toward the rea-r of a cranes rotating platform to minimize the traveling length of the Vehicle is disclosed in U.S. Patent No. 3,095,978 for use on a small truck mounted, luing crane. By contrast, the present invention is designed for use with heavy duty cranes of the type shown in U.S. Patent No. 2,529,454, which may have booms of 200 feet or more in length, wherein theitorque forces exerted on the boom foot are of such magnitude as to require a securely stabilized mounting. Also, these cranes require a boom stop cable, such as is shown in U.S. Patents Nos. 2,126,118 and 2,393,312, to prevent the operator from raising the boom higher than a predetermined safe angle. However, since the boom foot of the present invention is movable, a stop cable according to the prior art cannot be used with it because the cable would become fouled whenever the boom is moved to its traveling position. Accordingly, as a part of the present invention, a novel boom stop cable means is provided which keeps the boom stop cable taut at all times.

Summary ofthe invention The present invention relates to a boom handling apparatus for a crane boom mounted on a main frame wherein the toot of the boom is secured to a conveyor member adapted to move the boom foot between a stabilized working position near the front of the main frame and a traveling position near the back of the main frame.

In summary, the salient objects and advantages of the present invention are as follows:

To provide a crane with crane boom having a maximum Ireach.

To provide a crane with a lowerable boom having a minimum overall length when the boom is in its lowered position.

To provide a heavy duty crane wherein the foot of the boom has a stable working position and is movable to a traveling position so as to provide a minimum traveling length without reducing its eifective reach.

To provide a crane having a boom with a movable boom foot and a boom stop cable that is taut at all times.

To provide a heavy duty crane having a boom with a 4movably mounted foot that is stabilized in its working position to an extent comparable to the stabilization of a boom with a fixed mounted foot.

In the specification and the attached drawings several embodiments of the present invention are disclosed, and the invention and the manner and process of making and using the invention are described in such full, clear, concise and exact terms as to enable any person skilled in the art to which it pertains or with which it is most nearly connected to make and use it. However, let it lbe emphasized that the embodiments thus disclosed herein merely represent the best mode presently contemplated for carryin g out this invention, and that the invention is not limited Ito these specific embodiments. The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification.

Brief description of the drawings FIG. 1 is a side elevation of a crane employing the first embodiment of the present invention and with portions removed to show the lboom support and mounting structure with the boom in its operating position.

FIG. 2 is a top plan view of the embodiment shown in FIG. 1.

FIG. 3 is a side elevation of the embodiment shown in FIG. 1 with parts removed to show the -boom support and mounting structure with the boom in the traveling position.

FIG. 4 is a partial side elevation of the embodiment shown in FIG. 1 illustrating the boom stabilization means.

FIG. 5 is a front elevation in section taken along the line 5-5 of FIG. 4.

FIG. 6 is a top plan view in section taken along the line 6-6 in FIG. 4.

FIG. 7 is a front elevation in section of the novel boom stop cable drum of the present invention taken along the line 7--7 in FIG. 8.

FIG. 8 is a side elevation in section of the novel boom stop cable drum of the present invention taken along the line 8-8 in FIG. 7.

FIG. 9 is a side elevation partially in section of a crane employing a second embodiment of the present invention.

FIG. 10 is a top plan view of the embodiment shown in FIG. 9.

Description of the preferred embodiments In the side plan view of FIG. l, there is shown a conventional truck chassis 1 having wheels 2, and a truck cab 3 that is suspended on the front end of the chassis 1. A crane is mounted on the rear end of the truck chassis 1 and hydraulic outriggers 4 are provided to support and stabilize the rear end of the truck chassis 1 when the crane 5 is in operation.

A revolving frame 6, which is rotatably mounted on the rear end of the truck chassis 1, supports the operating mechanism and superstructure of the crane 5. The top plan view shown in FIG. 2 illustrates the unique arrangement of the operating mechanism. of the crane on the revolving frame 6. Housings 7 and 8 extend the length of each side of the revolving frame 6, defining a channel 9 between them down the middle of the revolving frame 6 in which a boom and related apparatus and structure are nested. The front of the housing 7 at the top of FIG. 2 is a crane cab 11 and behind the crane cab 11 is a control enclosure 12 containing the hydraulic valves, controls and the like for operating the crane 5. On the lower side of FIG. 2, the front portion of the housing 8 is an engine enclosure 13 containing a diesel prime mover, and behind the engine enclosure 13 is a pump enclosure 14, which contains the hydraulic pumps for operating the crane 5.

The boom 10 has wheels 15 on its top 16 to support the top 16 when the boom 10 is lowered to the ground. At the opposite end of the boom 10 is a bifurcated boom foot 17 having two sections 18 and 19 which are hinge mounted about hinge pins 20 and 21 to form articulated couplings 22 and 23. The other ends of the articulated couplings 22 and 23 are fastened on the ends of conveyor arms 24 and 25, respectively, each coupling 22 and 23 being made up of a pair of steel plate links 26, one of which is riveted, welded or otherwise fastened to each side of the ends of the conveyor arms 24 and 25.

The opposite ends of the conveyor arms 24 and 25 are secured to the ends of a torque tube 27, which is journaled in fulcrurn stands 28 that are mounted on the revolving frame 6. An hydraulic rotary actuator 29 is fastened through a driving connection (not shown) to rotate the torque tube 27 through about 180.

The articulated couplings 22 and 23 are shown in greater detail in FIGS. 4 through 6. The links 26 of each coupling 22 and 23 have aligned apertures 30 cut through them to receive cross heads 31 and 32 of T-bolts 33 and 34. The shanks 35 and 36 of the T-bolts 33 and 34 project through holes 37 and 38, respectively, in the revolving frame 6, and they have threaded nuts 39 and 40, respectively, or other tightening devices fitted onto them beneath the revolving frame 6. The cross heads 31 and 32 of the T-bolts 33 and 34 are supported above the surface of the revolving frame 6 by coil springs 41 and 42 which are mounted about the shanks 37 and 38. To secure the boorn foot 17 in the working position, as shown in FIGS. 1, 2, 4-6, the cross heads 31 and 32 of the T-bolts 33 and 34 will be rotated 90 from the position shown in those figures to a front-to-back alignment, so that the articulated couplings 22 and 23 will slide over the respective cross heads 31 and 32 to rest on the top surface of the revolving frame 6. Then the cross heads 31 and 32 are rotated back 90 into the position shown in the drawings so that they project through the apertures 30 in the links 26 of the respective couplings 22 and 23, and then the heads 31 and 32 are drawn down snugly by tightening the vnuts 39 and 40 on the ends of the respective Shanks 35 and 36 of the T-bolts 33 and 34. Thus, the boom foot 17 is securely stabilized to the revolving frame 6 to withstand any loads normally expected of cranes of this type.

Mounted toward the back end of the revolving frame 6 is a lowerable A-frame 43 having a pair of front legs 44 and a pair of back legs 45. The lowerable A-frame 43 shown in the drawings is the same as is described in detail in the copending application of Mario Pezzini for a A Frame Assembly for Mobile Cranes and the Like, Ser. No. 43,288, iiled on Apr. 18, 1966, and reference may be had to that application for a detailed description of the A-frame 43. For present purposes it will suh'ice to note that the back legs 45 of the A-frame 43 are rnade up of upper portions 46 and lower portions 47 which are linked together, respectively, by pins 48 in the upper portions 46 projecting through slots 49 in the lower portions 47. Lock pins 50 are inserted through aligned holes in the upper portion 46 and the respective lower portions 47 when the A-frame 43 is raised into the position'shown in FIG. l, to hold the back legs 45 against buckling. In order to lower the A-frame 43, the lock pins 50 are removed permitting the back legs 45 to break around the pivot pins 48 providing a knee action whereby the lower end of the upper portions 46 and the upper end of the lower portions 47 fall inwardly while the top of the upper portions l46 fall rearwardly as the front legs 44 lay back over the back legs 45. Other types of lowerable A-frames are known to the art and may be used in place of the lowerable A-frame 43 shown here. For example, hydraulic cylinders may be used as telescoping back legs.

A boom hoist drum S1 operated by hydraulic motors 52 is centrally mounted ytoward the back of the revolving frame 6. A boom hoist cable 53 extends from the boom hoist drum 51 up to a multipart suspension bridle 54 at the top of the A-frame 43, and the suspension bridle 54 in turn is connected to the boom top 16. Mounted in tandem in front of the boom hoist drum 51 in the channel 9 are an auxiliary working drum 55 driven by hydraulic motors 56 and a main working drum 57 turned by hydraulic motors 58. Cables 59 and 60, respectively, from the auxiliary working drum 55 and the main working drum 57 are extended to and over sheaves in the boom 10 to support a hook, a clam shell bucket, or some other tool.

Rotatably mounted on a shaft 61 supported on the front end of the revolving frame 6 are a pair of rollers 62 and 63. A pair of tracks 64 on the underside of the boom 10 are aligned with the rollers 62 and 63, respectively, and ride on the rollers 62 `and 63 when the lowered boom 10 is being drawn upwardly and rearwardly into the traveling position. A front view in section of these rollers is shown in FIG. 7. The rollers 62 and 63 are mounted on the shaft 61 by journal bearings 65 and 66, so as to rotate about the shaft 61. Between the rollers 62 and 63, a stop cable drum 67 is rotatably mounted on anti-friction bearings 68 and 69 about flanges 70 and 71 projecting axially inwardly from the center of the rollers 62 and 63, respectively. Inside of the stop cable drum 67 a return spring drum 72 is fastened to the stationary shaft 61. Between the inside of a stop cable drum 67 and the outside of the return spring drum 72 a coil return spring 73 is mounted with a ixed end 74 anchored to the stationary return spring drum 72 and a movable end 75 fastened to the stop cable drum 67.

A stop cable 76 is wound on the outside of the stop cable drum 67 with one end 77 secured to the stop cable drum 67 in a conventional manner, and the other end 78 secured to the boom 10. A cable guide 79 is mounted on the surface of the stop cable drum 67 and appears on the bottom of the drum in FIGS. 7 and 8. The stop cable 76 passes through the cable guide 79 a short distance from the end 77 that is fastened to the drum 67, and the cable guide 79 is secured directly in the middle of Ithe stop cable drum 67. The purpose of the guide 79 is to insure that when the stop cable 76 is extended to its limit, as is shown in FIGS. 7 and 8, the strain exerted by the boom 10 will be applied to the center ofthe stop cable drum 67. Immediately in front of and slightly lower than the stop cable drum 67 a fleet sheave 80 is mounted on a shaft 81 that is supported parallel to the boom roller shaft 61.

When the boom 10 is in its traveling position, extending over the cab 3 of the truck, the boom 10 is supported on a pair of rollers 82 that are resiliently mounted on snubbers 83 just behind the truck cab 3. When ythe boom 10 is in this traveling position, the boom hoist cable 53 and the suspension bridle 54 are relatively slack, and to support these a pan 84 is built on the top of the boom 10 to receive and hold the suspension bridle 54.

FIG. 1 shows a preferred embodiment of the present invention with the boom 10 in its normal operating position. To move the boom 10 from the operating position to the traveling position, the boom hoist drum 51 is first actuated to lower the boom into the position shown in broken lines, with the wheels on the top 16 of the boom 10 resting on the ground. When the boom .stabilizing means is released by loosening the nuts 39 and 40, or such other tightening means as may be used, on the Shanks and 36 of the nT-bolts 33 and 34, and then rotating the cross heads 31 and 32 of t-he T-bolts 33 and 34 so as to disengage the apertures 30 and the links 26 of the articulated couplings 22 and 23. Then the rotary actuator 29 is energized to begin turning the torque tube 27 in a clockwise direction as seen in FIG. 1. As the torque tube 27 rotates, it causes the :conveyor arms 24 and 25 fastened on its ends to rotate in the same direction, first lifting the articulated couplings 22 and 23 in an ahnost vertical direction and then swinging the couplings 22 and 23 and thus the boom foot 17 through an arc, which carries the boom foot 17 upward and rearward and then down again until it reaches the traveling position shown in FIG. 3. As the boom foot 17 is thus drawn upward and rearward, the boom 10 follows, and the tracks 64 on the underside of the boom 10 are lifted upward to rest on top of the boom rollers 62 and 63, supporting the boom 10 as it is drawn rearwardly. As the boom 10 is drawn upward onto the boom rollers 62 and 63, the wheels 15 and the top 16 of the boom 10 are lifted off the ground.

As the boom 10 is drawn upwardly andv rearwardly, the boom hoist drum 51 simultaneously draws in on the boom hoist cable 53 to prevent the boom hoist cable 53 and the suspension bridle 54 from becoming fouled. When the boom 10 has reached its rearmost position, the A- frame 43 is then lowered in the manner already explained, and the suspension bridle 54 is nested in the pan 84 on the top of the boom 10. Either before or after lowering the A-frame 43, the crane 5 may be rotated from the position shown in FIG. l to the position shown in FIG. 3, so as to bring the boom 10 over the top of the truck cab 3 so that the boom 10 will be resiliently mounted on the rollers 82 which are supported by the snubbers 83. After the counterweight is removed from the revolving frame 6 and Outrigger 4 retracted, the truck crane is ready for highway travel.

When the truck crane arrives at its working destination, the counterweight is remounted on revolving frame 6 and the outriggers 4 are set in a working position. The A-frame 43 is raised, and then the actuator 29 is energized from the hydraulic pumps to rotate the conveyor arms 24 and 25 back towards the front of the revolving frame 6 until the `articulated couplings 22 and 23 once again rest on the top of the revolving frame -6 over the boom foot stabilizing means, when the cross heads 31 and 32 of the T-bolts 33 and 34 of the boom stabilizing means may be reengaged through the apertures 30 as was explained above. When the boom hoist drum 51 is energized to draw up on the boom hoist cable 53 raising 4the boom 10 to the position shown in FIG. 1, as the boom 10 is raised, boom stop cable 76 is drawn from the stop cable drum 67, causing the stop cable drum 67 to rotate about the shaft 61. As the stop cable drum 67 rotates, it winds up the stop cable return spring 73 on the return spring drum 72. When all of the boom stop cable 76 is drawn from the stop cable drum 67, the boom 10 has reached its maximum safe angle and the boom stop cable 7-6 will prevent its being raised any further. When the boom 10 is then lowered, or when it is drawn rearwardly from the lowered operating position to the traveling position, the return spring 73 will unwind, causing the boom stop cable drum 67 to rewind the boom stop cable 76. Thus, as the boom 10 is raised, or lowered, and moved to and from its traveling position, the boom stop cable 76 is always taut and can never become fouled.

When the boom 10 is in the traveling position, it is nested in the channel 9 between the housings 7 and 8 on the revolving frame 6, and its weight is distributed between the revolving frame 6 and the rollers 82, which are mounted immediately behind the truck cab 3. Thus, a crane of the present invention presents a low silhouette, has its weight well centralized on the truck chassis 1 so as to be stable and safe to drive on the highway, and its length is minimized. To move the boom 10 from the traveling position to the working position, or vice versa, requires av minimum amount of labor in that the entire operation is powered and can be carried out by the crane operator. Of course, if a very long boom is to be used, sections of it will have to be removed for highway travel and re-inserted when the boom is to be worked.

FIGS. 9 and l0 show an alternative embodiment of the present invention utilizing different conveyor means for moving the boom foot 17 between the traveling position and the working position. Also, the alternative embodiment illustrates a variation in the mounting for the boom rollers 62 and 63. Otherwise, the structure of the two embodiments may be considered to be the same and the sarne reference numerals will be used for common structure.

The boom roller shaft 61 is mounted through a pair of upwardly canted members 85, which are secured on the ends of the sliding beam 86, which is mounted to be horizontally extended from and retracted into the revolving frame 6. The extension and retraction of the sliding beam 86 with the boom rollers 62 and 63 mounted on it can be effected manually, hydraulically of mechanically. By extending the sliding beam 86 with the boom rollers 62 and 63 outwardly, better leverage on thev boom 10 is achieved permitting the handling of a longer boom 10.

A pair of conveyor chains 87 and 88 are mounted about four pairs of sprockets 89, 90, 91 and 92, at least one of which is connected to be power driven. To move the boom foot 17 from the working position as shown in FIGS. 9 and 10 to the traveling position, the driven sprocket 89, 90, 91 or 92 is actuated to drive the conveyor chains 87 and 88 in the direction of the arrows in FIG. 9, carrying the boom foot 17 first upwardly and then rearwardly, until it arrives at the rearmost sprocket 89. To place the boom 10 in its working position, the procedure is reversed.

A coupling, such as the articulated couplings 22 and 23 described in connection with the first embodiment, may be used to link the boom foot 17 to the conveyor chains, and similar stabilizing means can be used to anchor the boom foot 17 in its working position. In any case, the invention is not limited to the specific conveyor means,

, linking means or stabilizing means shown, but, rather, is

the front of said revolving frame when said boom is in operating position and that is removed from said revolving frame and position near the back end of said revolving frame when said boom is in a traveling position;

' boom conveyor means mounted on said revolving frame,

having said boom foot attached to it, and being adapted to move said boom foot from said operating position to said traveling position; and

boom stabilizing means mounted on said revolving frame and adapted to positively anchor said boom foot to said revolving frame at a single fixed point independent of boom angle when said boom foot is in said operating position.

2. A boom handling apparatus for a crane as set forth in claim 1 wherein:

said boom conveyor means comprises a pair of spaced apart arms which are .pivotally mounted at one end near the back of said revolving frame, connected to an actuator to pivot said arms through an arc between the front and back ends of said revolving frame, and which have free ends opposite said pivotally mounted ends;

said boom foot is bifurcated; and

articulated couplings connect said bifurcated boom foot to said conveyor arms.

3. A boom handling apparatus for a crane as set forth in claim 1, wherein:

a coupling attaches said boom foot to said boom conveyor means and said coupling has at least one member attached to said boom conveyor means, which member is pivotally attached to said boom foot adapted to be engaged by said boom stabilizing means when said boom foot is in said operating position to anchor said boom foot to said revolving frame.

4. A boom handling apparatus for a crane as set forth in claim 1, wherein:

said boom and said boom conveyor means are centrally positioned on said revolving frame; and

equipment housings including a crane operators cub are positioned along each side of said revolving frame and said boom and boom conveyor means.

5. A boom handling apparatus for a crane as set forth in claim 1, wherein:

a boom stop cable has one end fastened to said boom to limit the angle to which the boom may be raised;

a spring load take-up reel is mounted on the front end of said revolving frame and another end of said boom stop cable is fastened to said spring loaded take-up reel to be normally wound on said spring loaded take-up reel;

said spring loaded take-up reel being so arranged that spring loading of the reel occurs as the boom stop cable is pulled from said reel by movement of said boom and said spring loading rewinds said boom stop cable when movement of said boom releases said boom stop cable.

`6. A boom handling apparatus for a crane as set forth in claim 1, wherein:

wheels are mounted on the top of said boom to support it when said boom is lowered; and

rollers are mounted on the front of said revolving frame beneath said boom so that when said boom is lowered and drawn toward the back of said revolving frame by said boom conveyor means said boom will ride first on said wheels until said boom engages said roller and said boom will then ride on said rollers until it reaches said traveling position.

7. In a crane having a machinery platform and a tiltable boom the combination therewith of:

arm means having one end thereof pivotally mounted toward the rear of said platform for swinging the opposite, outer end of the arm means in a vertical, fore and aft plane toward and away from the front of the platform;

a pivoted connection between the boorn foot of said boom and the outer end of said arm means for swinging the boom foot with said outer end; and

power means connected with said arm means to pivot the same between (i) a forward position placing both the outer end of the arm means and the boom foot at the front of said platform in a boom operating position, and (ii) a rearward position placing the boorn foot in a traveling position toward the rear of said platform.

8. In a crane in accordance with claim 7 having cable drums mounted on said platform in positions midway between the sides of the platform, and said arm means swinging its outer end and the boom foot up and over said cable drumswhen moving the boom foot from the operating position to the traveling position.

9. A crane in accordance with claim 8 having an operators cab and housings located along the sides of said platform to form a central, fore and aft extending channel for the platform through which said arm means is swung and in which the boom is cradled when the boom foot is in said traveling position.

References Cited UNITED STATES PATENTS 2,126,118 8/1938 Kelley 212-39 2,393,312 1/ 1946 Davenport 212-39 2,529,454 11/ 1950 Marcantonio 212-144 3,095,978 7/1963 Boyer 212-145 3,306,470 2/1967 Green et al 212-144 3,335,877 8/1967 Pezzini 212-144 ANDRES H. NIELSEN, Primary Examiner. 

